1. Field
This disclosure is generally related to the distribution of digital content. More specifically, this disclosure is related to pre-calculating and verifying properties of a message in a named data network, and delegating the burden of this property validation to border routers within a trust domain.
2. Related Art
The proliferation of the Internet and e-commerce continues to fuel revolutionary changes in the network industry. Today, a significant number of information exchanges, from online movie viewing to daily news delivery, retail sales, and instant messaging, are conducted online. An increasing number of Internet applications are also becoming mobile. However, the current Internet operates on a largely location-based addressing scheme. The two most ubiquitous protocols, the Internet Protocol (IP) and Ethernet protocol, are both based on location-based addresses. That is, a consumer of content can only receive the content by explicitly requesting the content from an address (e.g., IP address or Ethernet media access control (MAC) address) closely associated with a physical object or location. This restrictive addressing scheme is becoming progressively inadequate for meeting the ever-changing network demands.
Recently, content centric network (CCN) and named data network (NDN) architectures have been proposed in the industry. CCN brings a new approach to content transport. Instead of having network traffic viewed at the application level as end-to-end conversations over which content travels, content is requested or returned based on its unique name, and the network is responsible for routing content from the provider to the consumer. Note that content includes data that can be transported in the communication system, including any form of data such as text, images, video, and/or audio. A consumer and a provider can be a person at a computer or an automated process inside or outside the CCN. A piece of content can refer to the entire content or a respective portion of the content. For example, a newspaper article might be represented by multiple pieces of content embodied as data packets. A piece of content can be associated with meta-data describing or augmenting the piece of content with information such as authentication data, creation date, content owner, etc.
In a CCN or NDN, content objects and interests are identified by their names, which are typically hierarchically structured variable-length identifiers (HSVLI). Generally, interests and content objects travel through a number of links before they can reach their destination. In CCN, specialized hardware might be required to calculate and verify certain properties potentially at line rate. These operations include, but are not limited to, a hash of a content object, signature verification when an embedded key is present, a hash of an interest, and other properties that can communicate state information within a trust domain. While some routers (such as border routers) in a CCN trust domain are designed for these computationally expensive line rate calculations, other routers (such as backbone core routers) in the same domain could experience significant delay if required to calculate and verify these various properties.